P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient
All Star
Joined: Nov 2004
Posts: 951
Likes: 0
From: Kankakee, IL
RE: P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient
From the 2004 FSM
EGR MONITOR (if equipped)
The Powertrain Control Module (PCM) performs
an on-board diagnostic check of the EGR system.
The EGR monitor is used to test whether the EGR
system is operating within specifications. The diagnostic
check activates only during selected engine/
driving conditions. When the conditions are met, the
EGR is turned off (solenoid energized) and the O2S
compensation control is monitored. Turning off the
EGR shifts the air fuel (A/F) ratio in the lean direction.
The O2S data should indicate an increase in the
O2 concentration in the combustion chamber when
the exhaust gases are no longer recirculated. While
this test does not directly measure the operation of
the EGR system, it can be inferred from the shift in
the O2S data whether the EGR system is operating
correctly. Because the O2S is being used, the O2S
test must pass its test before the EGR test. Also
looks at EGR linear potentiometer for feedback.
However as previously stated may not have one as the 2004 FMS on the Engine does not list the code. I would not erase it and ask Chrysler how the heck that is possible. If you do nto have and EGR system that would most definitely be a Manufacturers DEFECT!!!! See if they will update the PCM for FREE!!!!
EGR MONITOR (if equipped)
The Powertrain Control Module (PCM) performs
an on-board diagnostic check of the EGR system.
The EGR monitor is used to test whether the EGR
system is operating within specifications. The diagnostic
check activates only during selected engine/
driving conditions. When the conditions are met, the
EGR is turned off (solenoid energized) and the O2S
compensation control is monitored. Turning off the
EGR shifts the air fuel (A/F) ratio in the lean direction.
The O2S data should indicate an increase in the
O2 concentration in the combustion chamber when
the exhaust gases are no longer recirculated. While
this test does not directly measure the operation of
the EGR system, it can be inferred from the shift in
the O2S data whether the EGR system is operating
correctly. Because the O2S is being used, the O2S
test must pass its test before the EGR test. Also
looks at EGR linear potentiometer for feedback.
However as previously stated may not have one as the 2004 FMS on the Engine does not list the code. I would not erase it and ask Chrysler how the heck that is possible. If you do nto have and EGR system that would most definitely be a Manufacturers DEFECT!!!! See if they will update the PCM for FREE!!!!
